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Sensory thresholds
Sensory threshold is a theoretical concept used in psychophysics. A stimulus that is less intense than the sensory threshold will not elicit any sensation. Several different sensory thresholds have been defined; *'Absolute threshold:' the lowest level at which a stimulus can be detected. *'Recognition threshold:' the level at which a stimulus can not only be detected but also recognised. *'Differential threshold' the level at which an increase in a detected stimulus can be perceived. *'Terminal threshold:' the level beyond which a stimulus is no longer detected. The concept can be applied to all senses as in: Auditory thresholds *'Auditory absolute threshold:' the lowest level at which a stimulus can be detected. *'Auditory recognition threshold:' the level at which a stimulus can not only be detected but also recognised. *'Differential threshold' the level at which an increase in a detected stimulus can be perceived. *'Auditory terminal threshold:' the level beyond which a stimulus is no longer detected. Olfactory thresholds *'Olfactory absolute threshold:' the lowest level at which a stimulus can be detected. *'Olfactory recognition threshold:' the level at which a stimulus can not only be detected but also recognised. *'Differential threshold' the level at which an increase in a detected stimulus can be perceived. *'Olfactory terminal threshold:' the level beyond which a stimulus is no longer detected. Vibrotactile thresholds *'Vibrotactile absolute threshold:' the lowest level at which a stimulus can be detected. *'Vibrotactile recognition threshold:' the level at which a stimulus can not only be detected but also recognised. *'Differential threshold' the level at which an increase in a detected stimulus can be perceived. *'Vibrotactile terminal threshold:' the level beyond which a stimulus is no longer detected. Visual thresholds *'Visual absolute threshold:' the lowest level at which a stimulus can be detected. *'Visual recognition threshold:' the level at which a stimulus can not only be detected but also recognised. *'Differential threshold' the level at which an increase in a detected stimulus can be perceived. *'Visual terminal threshold:' the level beyond which a stimulus is no longer detected. In aviation Aviation use. ﻿When related to motion in any of the possible six degrees of freedom (6-DoF), the fact that sensory thresholds exist is why it is essential that aircraft have blind-flying instruments. Sustained flight in cloud is not possible by `seat-of-the-pants' cues alone since errors build up due to aircraft movements below the pilot's sensory threshold, ultimately leading to loss of control. * In flight simulators with motion platforms, the motion sensory thresholds are utilised in the technique known as `acceleration-onset cueing'. This is where a motion platform, having made the initial acceleration that is sensed by the simulator crew, the platform is re-set to approximately its neutral position by being moved at a rate below the sensory threshold and is then ready to respond to the next acceleration demanded by the simulator computer. See also *Dark adaptation threshold *Detection theory *Critical flicker fusion threshold *Odor detection threshold *Perception *Perceptual measures *Psychophysics *Sensory analysis *Threshold detection Category:Perceptual measures Category:Sensory thresholds